Grinding wheel dresser



April e, `19.415.

E. A.'OVERSTEDT GRINDING WHEEL nRssER' Filed Aug. 9. 1944" 4sheets-sheet 1 April 6, 1948.

E. A. ovERsTEDT 2,439,263 GRINDING WHEEL DRESSER l Filed Aug. 9v, 1944Ap 76, A194s.

E. A. ovaRs'l-EDT GRINDING WHEEL DRESSER Filed Aug. 9, 1944 4sheets-'sheet s IN VEN TOR.

Patented Apr. 6, 1948 GRNDING WHEEL DRESSER Ernest A. Overstedt,Detroit, Mich., assigner to Louella May Dalzen, William Russel Dalzen,and Frederick Roy Dalzen, trustees. Dalzen Y Trust, Detroit, Mich.

Application August 9, 1944, Serial No. 548,701

12 Claims. l

This invention relates to dressers for grinding wheels and moreparticularly to a thread grinding wheel dresser. The present inventionprovides a dresser for the two flanks of a grinding wheel as well as thetop peripheral edge thereof.

It is the object of the present invention to provide a dressingmechanism employing a plurality of dressing diamonds adapted to dressthe grinding wheel flanks from 15 to 90 included angle. and the top edgeof the Wheel from a flat to an angle of approximately for a sloping rootof thread. y

It is the further object herein to provide a plurality -of separatelysupported pivotally mounted dressing diamonds each adapted toprogressively sweep one of the grinding wheel edges rst in one directionand then the other.

It is the further object of this invention to provide means for slidablysupporting the dresser housing with respect to the Vgrinding wheeltogether with means for effecting intermittent regular adjustments ofthe dresser relative to said wheel.

Further objects will be seen in the various arrangements of elem-entsand their combinations forming a part of said dresser as set out in thefollowing specication and claims in connection with the appendeddrawings of which- Fig. 1 is a front elevational view of the Wheeldresser. l

Figl. 2 is an elevational section of line 2- 2.of Fig.

Fig. 3 is a right end elevational view thereof.

Fig. 4 is a plan view thereof.

Fig. 5 is an elevational section on line 5 5 oi Fig. 2.

Fig. 6 is an elevational section on line Fig. 4.

It will be understood mthat the.` above iigures are merely illustrationsof a preferable embodiment of the invention, and other `embodiments arecontemplated within the scope of the inven` tion as set out in theaccompanying claims.

In the drawings, the grinding wheel dresser consists of housing II withremovable front plate I2 as shown in Fig. 1. `In Fig. 4 parallel 'spacedball tracks I3` are shown joined to housing Il, and adaptedV forvertical adjustments relative to s-s cf corresponding spaced' adjustabletracks I4 formpensate for 2 ing a part of vertical slide I5, with spacercarried balls IB interposed between said tracks.

Vertical slide screw Il shown in Fig. 6 supported by housing II withbushing I8 interposed, threadably engagesv nut 34 secured withinvertical slide I5 whereby rotation` of screw I1 effects verticaladjustments of housing II relative to said vertical slide. t

Said slide is further adjustably carried by supporting bracket I9 bymeans of manually adjustable screw 20 rotatably carried by said bracketand threadably engaging vertical slide I5.

The latter slidably engages said bracket by the dovetail connection 2|`with vertical slide gib 22 interposed and with gib adjusting screw 23for taking up any slack therebetween, as shown in Fig. 4.

Bracket I9 which thus adjustablly carries dresser housing II, thoughbroken away in Fig. 4, is adapted for attachment to the grinding wheelsupporting head not shown, of for instance, a thread grinding machine.

'I'hus while said bracket moves together with 4feed. movements of thegrinding wheel yet vertical adjustments of the dresser housing areprovided relatively toA said grinding wheel to comchanges in wheeldiameter due to wear and to dressing of the peripheral edges thereof.

Dresser housing feeding Housing II is adapted to manual feeding relativeto the grinding wheel by means of ratchet wheel shaft 24 rotativelymounted upon housing Il within bushings 25 therein. Hand wheel 26 on oneend of said shaft permits manual rotation thereof as well `as of bevelgear 21 at its other end which is inmesh with `corresponding bevel gear28 secured upon vertical slide screw I'I. Thus actuation of said handwheel effects vertical adjustments oi dresser housing I I withrespect'to vertical slide I5, as well as with respect to grinding wheel29. A

Housing II is also adapted to accurate feed adjustments by means of`electrically actuatedV solenoid 30 best shown in Figs. 3 and 4. Link 3linter-connects said solenoid and feed ratchet lever 32 by pins 33; whilesaid lever is pivotally mounted upon ratchet wheel collar `34 `forming apart of ratchet wheel 35.

The latter keyed at 36 to shaft 24 is intermittently actuated by pawl 31in Fig. 3 pivotally carried by stud 38 extending from adjacent the endof lever 32 as shown Vin Fig. 1. Fig. 3 shows compression spring 39joined to the end of pawl 31 and with its other end secured to the endof lever 32 for resiliently maintaining pawl 31 in engagement withratchet wheel 35.

A second coil spring 40 is secured at one end at 4| to lever 32 whilethe other end is anchored at 4Z to dresser housing whereby said lever isresilientl-y tilted counter-clockwise.. .Ont actuation of solenoid '36by a suitable hand switch, link 3| is projected downwardly effecting aclockwise pivotal movement of lever 32 and a corresponding translatorymovement of pawl 31 to the right resulting in rotary movement of ratchet35 and shaft 24. I Y

Thus by actuation of so1enoi'd'3-6' accurate and' regular adjustments ofthe dresserghousing may be effected relative to grinding wheel 26.Adjust able stop d3 shown in Figs. 1 and 3 adjustably supported by stud44 on housing is adapted'to act as a stop for ratchet lever 32 limitingthe resilient return movement counterclockwise thereof. When set asshowni-.n Fig. 1 surface 45 is engaged by said. lever permitting .onlyenough return of pawl 31 so that only one ratchet tooth is passedthereby.` Consequently actuation of solenoid 36 will result in aone-thousandth of an inch feed of dresser housingvl With stop i3adjusted angularly clockwise itis seen that lever 32 can return forengagement with stop surface 46 permitting4 pawl 31 to pass 'over twoteeth'fof ratchet wheel 35 so that upon the next actuation of said DaWlthe dresser housing feed will be two-thousandths of an inch.

Stop plunger 4&1 inFig. 3 is resilientl'y urged by adjustable spring 48into cooperative engagement with stop 43 within-eitherop'e'ning d6or'ilv Fig.

Y l for maintaining said stop in either of the two adjustments referredto.

Dresser feeding as above described may be thus effectedfor eithersuccessive one-thousandth of an inch feed or successive two-thousandthsof an inch feed upon each actuation of solenoid 36 accompanied bydownward movement -oflink 3|.

t is understood, however, that other adjustments are Apossible merely bychanging stp"4`3 and its surfaces. The important featureV herein residesin the fact that the returnsweepofpawl 31 over ratchet wheel 35 iseffectivelyregulated so. that one or twote'eth 'are encompassed by saidpawlwhen actuated by lever 32. l

Diamond dressing' mechanism For actuating the dressing mechanisme.constant speed electric motor is. employed secured Within dresserhousing if as. shown in'Figs. 1, 3 and 4. This motor is preferably agearreduction motor with an output of two to four revolutions per minute. Itis contemplated, however, that any other type of motor would also besuitable. Rotatable output shaft 52, Fig. I, has a crank 53y thereoncarrying an oi centersleeve 5d, Fig. 3, upon which the upper end. ofconnecting rod 55 is pivotally secured. y

Sleeve 56 secured to pivotal'oper'atingarm 51 is pivotally joined to thelower end of connecting rod 55. Thus asngleirotation ofV cran-k 53 onmotor 5| elects a reciprocable arcuate movement of operating arm 51.Arcuately reciprocabl-e arm 51 is joined to the diamondarm/sdriving'disc 58 by key 59 as shown in Fig. 2.- with spring 60 interposedtherebetween. j a Y Shaft 6| secured to cover plate I2 by threaded.

nut 62, extends through said plate providing a support for driving disc58 upon which it is reciprocably and arcuately journaled. Collar IE3provisioned on the end of arm 51 threadably engages shaft 6| and issecured thereby by set screw 64. Thus reciprocable arcuate movements areimparted to diamond arms driving disc 56.

Referring to Fig. 2 bracket 65 for the top diamond arm is carried uponthe inner dovetail surface 65 of cover plate |2 which is arcuate in formFig. 5 lto correspond with. arcuate adjustment slot 61', Fig. '1,forme-d therein. Arcuate clamp 38 interposed between cover plate I2 andbracket 65 is employed together with clamp screw 69 for securing saidbracket either in a vertical position or in'an. adjusted angularposition relative to plate l2.

Setting plug' 1U secured to bracket 65 extends outwardly through arcuateslot 61 providing means Afor accurately indicating the arcuate posiption of said bracket.`

Hollow bracket with cover plate 1| has secured-therein bushing 12through which is rotatably journaled diamond arm carrying shaft 13.Plate 14| supports shaft 13 with connecting screw l5, there being acoiled spring interposed between said bracket and shaft supportingplate. 14.

Top diamond carrying'` arm 16 issecured upon the lower end. of rotatableshaftl1'3 with washer il interposed between said arm andv bushing 12.Head 18 O'n the end O'f af'ni T6 has a transverse opening foradjustablyv retaining diamond' holder i9 secured thereinby set-screw 8U.there being a suitable diamond edge 8|' upon tl'ieLlower end .of saidholder. V Y

The opposite end of arm T6 is bifurcated at 8.2 (only one of saidbifurcations appearingfinthe section, in Fig.y 2) for receivingspherical ball member 33 upony the inner end of drive pin 8'4. Thelatter projects through a corresponding opening in reciprocableoperatingl disc 58'- and` is secured thereto by nut 85. 1 Y Y By meansof ball 83 a Yuniversal connection is effected between reciprocableoperating disc 58 and the top: diamond arm 16, whereby an arcuatereciprocable movement of operating disc 5a effects a correspondingarcuate reciprocable movement of the top diamond arm 16 and itssupporting pivotal shaft 13'. In turn an Varcuate reciprocable sweepingmovement of diamond 8| is effected with respect to the top edge of thegrinding` wheel sought toV beV dressed, as for instance, grinding wheel2.9in Fig. 5.

As above explained bracket 55' is angularly ad- J'ustable, ychangingtheE angle of sweep of. diamond 8|. However such adjustment in no wayaffects the arcuate movement of diamond-arm 'i6 because of theuniversal: ball connection between said diamond arm, and the drivingdisc 53.

As' shown in Fig. 5' a separately supported right hand diamond arm 86 isshown pivotally supported from bracket 61 by a suitable shaft carriedthereby in the manner described in detailpw'ith respect to bracket 65 inFigi 2,

Correspondingclamp screws G9 permit-arcuate angular .adjustmentsofbracketS-l with respect to arcuate dovetail slide 66 formed upon ntheback of cover plate f2. i Similarly a setting plug' 68 is secured tobracket' 8T and projects outwardly through ccrresponding arcuate acl-justment opening sem @over plate far'ig. 1.

Right diamond amil se with head 9c at one me afjllstbly Supports?diam-ond holder 9| Vwith its diamond end 92 wliielris adapted Vtoreciprocabl'e casacca sweeping movement relative to one of the inclinededges oi grinding Wheel 29. It is understood that regardless of theangular adjustment of bracket 81 the sweeping movement of diamond 92 isalways in a plane perpendicular to the central axis of said bracket.

As above described in detail, the inner end of diamond arm 86 islikewise bifurcated for receiving ball member 93 on the inner end ofdrive pin 94, shown in Fig. 1, but which is similar to drive pin 84shown in Fig. 2.

Drive pin 94 projects through a corresponding opening in cover plate l2,Fig. 1, and is secured to reciprocable driving disc 58 by nut 95.Similarly, by the universal connection between reciprocable driving disc58 and right diamond arm 86 it is seen regardless of the angularadjustment of bracket 81, that arcuate reciprocable movement of drivingdisc 58 effects a corresponding planular arcuate reciprocable movementof rightvdiamond arm 85 as well as diamond 92 carried thereby.

Fig. 5 also shows a corresponding separately supported left hand diamondarm 93' pivotally supported by bracket 94 by a suitable shaft carriedthereby as above described.

Corresponding clamp lscrews 69 permit arcuate angular adjustments ofbracket 94 with respect to arcuate dovetail slide 66 formed upon theback of cover plate |2. Similarly setting plug 95, Fig. l, is secured tobracket 94 and projects outwardly through corresponding arcuateadjustment opening 95 in cover plate l2.

Left diamond arm 93 with head 91 at one end adjustably supports diamondholder 98 with its diamond end 99 which is adapted to reciprocableplanular sweeping movement relative to the other inclined edge ofgrinding wheel 29.

The inner end of diamond arm 93' is likewise bifurcated for receivingball member |00 on the inner end of drive pin |0|, shown in Fig. l, butwhich is similar to drive pin 84 shown in Fig. 2. Drive pin |0| projectsthrough a corresponding opening in cover plate I2 and is secured toreciprocable driving disc 58 by nut |02.

Similarly by the universal connection between driving disc 58 and leftdiamond arm 93' it is seen, regardless of the angular adjustment ofbracket 94, that arcuate reciprocabl-e movement of driving disc 58eiects a corresponding planular arcuate reciprocable movement of leftdiamond arm 93 as well as diamond 99 carried thereby.

From the above it is seen that arcuately reciprocable diamond armdriving disc 58 has adjustably secured thereto the three diamond armdrive pins 84, 94, and 0| respectively secured by nuts 85, 95 and |02.

All of these pins project inwardly through the semi-circular opening |03in cover plate |2 terminating respectively in the three sphericalmemberr 83, 93 and |00 shown in dotted lines in Fig. 5.

Each of said members respectively joins the three diamond carryingpivotal arms 16, 86 and 93 being inserted within the correspondingbifurcations in their ends.

Thus the arcuate reciprocable movement of driving disc 58 is adapted toeffect corresponding reciprocable movements of each of the diamondcarrying arms. By virtue of the separate universal driving connectionsbetween said disc and each of said arms it is seen that the arcuatereciprocable movement of said disc effects separate planular reciprocalsweeping movements of each of said diamond carrying arms with respect toone of the edges of grinding wheel 29.

\ It will be noted as each of said arms is pivotally supported from theadjustable brackets 65, 81 and 94 by the Apivotal shafts therein, thatthe `movements of said arms regardless of the angular adjustment oftheir supports is limitedto reciprocable planular movementsperpendicular to the axes of said brackets.

Consequently sweeping reciprocable planular movementsofeach of saiddiamonds 8|l, 92 and 99 are effected relative to the three peripheralsurfaces of grinding wheel 29.

Because of the rocking movement or driving disc 58 it is seen thatdiamond y92 engages the wheel at its lowest peripheral point sweeping upand diamond 8| engages the left top edge of the wheel 29, viewing Fig.5, sweeping to the right. At the same time diamond 99 engages the wheelat its topV edge-and sweeps angularly downward. On thereturn arcuatemovement of disc 58, the reverse is truewith each of said diamonds 99,8| and 92 simultaneously sweeping over the surfaces of thegrinding Wheelcorresponding thereto.

Referring to Figs. 1, 3 and 4, a limit switch case |04 is shown securedat |05 upon the front of motor 5| above crank 53 rotated thereby.Limit'switch |06 provisioned withincase |04, as shown in Fig.\3, hasacentral actuating means |01 for said switch which depends downwardlythrough bottom cover plate |08. Said switch controls by suitable wiring,not shown, stopping of motor 5| governing the dressing operation. In thelowestposition of actuating means lill, and when released to Vassumethat position, switch |06 permitsA operation of said motor. However withmeans] 01" elevated the switch stops the motor. Crank 53 has a centralprojecting switch actuating means |09 adapted to operably engage switchactuating means 01 each time said crank completes a revolution. Thus onone revolution of crank 53 one reciprocable sweeping movement ofthedressing diamonds is effected and the motoris then stopped as crankmeans |89 engages switch actuating means |01 projecting the sameupwardly.

Itis understood that motor 5I can be again restarted for anotherdressing operation by a suitable switch independent of limit switch |06.Naturally restarting of motor 5| effects a release of switch actuatingmeans |01. Consequently it is seen that the sole purpose of limit switch|96 is to stop motor 5| at the end of one revolution thereof.

Again referring to Fig. 1 stationary setting plugs ||0 are shownprojecting outwardly from cover plate |2. These plugs provide accuratemeasuring points for obtaining accurate adjustments ofany or allv ofdiamond arm bracket adjustment plugs 95, 10 andV 88.

Having described my invention reference should now be had to the claimswhich follow for determining the scope thereof.

I claim: t

V1. Agrinding wheel dresser comprising a heusn ing, a plurality ofseparately mounted diamond supporting means pivoted thereon, eachadapted to sweeping dressing movementsrelative to one of the peripheraledges of said grinding wheel, a reciprocable disc on said housinguniversally joined to each of said supporting means for effectingalternate clockwise pivotal movements thereof and reversed alternatecounter-clockwise pivotal movements thereof, and reciprocal meanspivotally joined to said disc.

2; A grinding wheel dresser comprising a housing, a plurality ofseparately mounted angularly adjustable diamond supporting means pivotedcasacca thereon, each. adapted to sweeping dressing movements'V relativetoene oi the peripheral edges of said grinding wheel, areciprocable discon. said housing universally joined` `to each o said supporting meansfor effecting reciprocable pivotal movements thereof, and reciprocalmeans pivotally joinedy to said disc, whereby slight substantiallyinstantaneous reciprocalmovements thereof effect a complete reciprocaldressing operation.

3. A grinding wheel dressercomprising a housing, a plurality of.radially spaced` separately mounted brackets thereon,- diamondsi-ipportingfv means pivotally carried by each bracket and adapted tosweeping dressing movements relative to one of the peripheral edges ofsaid grinding wheel, reciprocable disc on said' housing. universallyjoined to each of said supporting means for eiecting reciprocablepivotal movements thereof, and reciprocal means pivotally joined to saiddisc and adapted on reciprocal movementthereof to effect acompletereciprocaldressing operation.

4. A grinding wheel dresser comprising-a housing, a plurality ofradially spaced separately mounted brackets thereon,.,a top diamond arm,a right hand diamond arm, and al left hand diamond arm pivotally carriedby said brackets with dressing diamonds depending from the ends thereoffor relative sweeping engagement with the peripheral edges ofsaid-grinding wheel, a pivotal reciprocable drivingdisc on said housinguniversally j oined. separately to the opposite ends of each of saiddiamond arms for effecting reciprocable pivotalmovements thereof, andlongitudinally reciprocal meanspivotally joined tosaid disc foreffecting reciprocal movement thereof, and adaptedon. reciprocal.movement thereof to effect a complete reciprocal dressing operation.

5. A grinding wheel dresser comprising a housing, a plurality ofangularly adjustable radi-ally spaced separately mounted bracketsthereon, a top diamond armr a right hand diamond-arm, and a left handdiamond arm. pivotally carried by said brackets with dressing diamondsdepending from the ends thereof` for relative sweeping engagement withthe peripheral edges of said grinding wheel, a pivotal reciprocabledri-ving disc on said housing,- and. radially spaced transverse drivepins carried by said driving disc and universally joined to the oppositeends of each of said diamond arms for eiiecting reciprocable pivotalmovements thereof.

6. A grinding wheel dresser comprising a housing, a plurality ofvangularly adjustable radially spaced separately mounted bracketslthereon, a top diamond arm., a righ-t hand diamond. arm, and. a leftlhand diamond armA pivotaIl-.y carried by said brackets with-dressingdiamonds depending from the ends thereof. for yrelative sweepingengagement vvithA the peripheral edges of. said grinding wheel, apivotal reciprocable driving. disc on said housing, radially spacedtransverse drive pins carried by said. driving. discand universallyjoined to the opposite ends. of eachof said-l diamond Aarms foreffecting reciprooable Vpivotal movements thereof.V and adjustmentsetting plugs carried by said brackets andextending outwardly throughsaidv housing 7. A` grindingwheelldresser comprising. a housing, aremovable cover plate thereon: having an arcuateA dovetail'y ange withinAsaid housingF a plurality of radially spaced brackets adjustablycarried upon said angea top diamond arm, a right hand diamond arm, and alefthand diamond arm Ypivotally carried :by said brackets with dressingdiamonds depending from' the `ends thereof for separate relative.sweeping engagementvvith the peripheral edges of said grinding wheel.. areciprocable driving disc pivotally carried upon theoutside of saidcover plater and radially spaced transverse drive pins. carried by saiddisc, projecting through said cover plate, and universally joined. tothe opposite ends of each of said, diamond arms for effectingreciprocable pivotal movements thereof..

8. A grinding wheel dresser comprising a housing, a plurality ofseparately mounted diamond supporting means pivoted thereon, eachadapted to sweeping dressing movements relative to one of the peripheraledges of said grindingV wheel, pivotallly reeiprocable means onsaidhousing. and radically spaced drive means carried -by saidreciprocalmeans and universally joined toeach of saidsupporting meansfor effecting reciprocable pivotal movements thereof, and an actuatingreciprocable connecting rod joined to said reciprocable means, wherebyslight substantially-instantaneous reciprocal movements of said pivotalmeans effect a complete reciprocal dressing operation.

9. A grinding wheel dresser comprising. a housing, a plurality ofseparately mounted diamond supporting means pivoted thereon, each.adapted to sweeping dressing movements relative to one of the peripheraledgesof said grinding wheel, reciprocalole means on said housing., andradially spaced drive means carried by said. reciprocal means anduniversally joined to each of said supporting means for effectingreciprocable pivotal movements thereof, an actuating reciprocableconnecting rod pivotally join-ed; at once-nd to said reciprocable means,and a motor dri-veri crank-.eccentrically and pivotally joined to theother end' of said connecting rod.

l-O. A grinding Wheel dresser comprising a` housing, a plurality ofseparately mounted diamand supporting means pivoted thereon each adaptedt-o sweeping dressing movements relative to one oi the peripheral edgesof said grinding wheel, reciprocable means on said. housing, andradially spaced drive means carried'by said reciprocal means anduniversally joined tofeach of saidsupporting means for effectingreciproca.- ble pivotal movements thereof, an actuating reclprocableconnecting rodrpivotally joined at one end toy said reciprocable means..a motor driven crank eccentrically and pivotal-ly joined to the otherend oi said connecting. rod, and a: motor switch actuated by said crankfor limiting the sam-e to one revolution.

ll. A grinding wheel dresser comprising; a housing, a plurality ofseparately mounted; diamond supporting means pivoted thereon, eachadapted. to sweeping dressing movements relative to oneot the peripheraledges of said; grinding. wheel; reci-procableymeans on. said housing,radi-y a-.lly spaced drive means carried by said.' reciprocable' meansuniversally' joined to'each of sai-d supporting means foreifectingreciprocable pivotal movements thereof, anelectricrmo'tor onhousing`, arotatable crank drivenY thereby, means interconnecting said'reciprocable Nmeans and' said crank', and amotor switch actuated by saidcrank forV limiting the' same to one revolution.

122 A. grinding Wheel ydresser comprising a housing., rotatable threadedmeans carried Yby said' housing for effecting-adjustments of saidhousing relative to said grinding wheel?, arctatable shaft operably*jo-ined to said threaded ERNEST A. OVERSTEDT.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Number Name Date Brown Sept. 14, 1920 DeLeeuw Apr. 17, 1928 Flanders Mar. 1, 1932 Snarry Aug. 14, 1934 StewartFeb. 16, 1943 Snader July 4, 1944 Schantz Apr. 16, 1946 FOREIGN PATENTSCountry Date Germany July 116, 1913

